Double-decked grating-paved street



May 30, 1939- B. A; PRINCE I 2,160,315

DOUBLE-DECKED GRATING-PVED STREET Filed sept. 1'2, 193e 2 sheets-sheet 1IIIllIlIIllllIllIllllIIIlllllllllllllllllllllllllllflllllllIIlIlllllllllllllllllllllllllll!!! l' I I ,l

May 30, 1939. l B., A. PRINCE 2,160,315

I DOUBLE-DECKED GRATING-PAVED STREET Filed Sept. 12, 1936 2 Sheets-Sheet2 f ATTORNEY Patented May 30, 1939 UNITED STATES `PATENT OFFICEDoUBLE-DECKED GRATING-PAVED STREET Burton A. Prince, Westfield, Mass.,assigner to Walter E. Irving, Glenbrook, Conn.

Application September 12, 1936, Serial No. 100,436

11 Claims.

' ing the pavement Vof such main arteries of trac in smooth condition,and the cost and trouble of cleaning them, especially after a suddenaccumulation of snow and ice, are well known. The inconvenience andexpense of digging up underground pipes and removing and replacingordinary forms of pavement are equally notorious as well as is thefrequent occurrence of serious traic accidents caused bymotor carsskidding on the slippery and crowded roadways. Furthermore thedelayscaused by congestion of the trafc have long been a serious `matterand an important object of my invention is to double the capacity ofexistingrights of way, Without the erection of unsightly elevatedstructures which would render heavy damages collectible from the city byabutting property owners.

vAll these di'iculties can be avoided by the use of the presentinvention which consists essentially in lowering the surface of theearth under the existing street level a sufficient distance, installingat the street grade an open mesh grating of special type adapted to forma non-skid road surface for the traflic and another grating roadway inthe trench so formed at a depth sutcient to leave headroom for a secondstream of motorized traino thereover, preferably Vleaving enough roomunder such lower grating to ensure automatic drainage and clearanceduring and after any ordinary snowfall and to permitfmen to workon theexposed or .buried pipes and sewage conduits, while providing properdrainage for the surface of the .ground beneath so that all Adirt andsnow falling through said grating can be flushed into the storm sewersbyv streams of water from the hydrants.

The type and weight of grating best vsuited for use with my presentinvention are illustrated and described in Patent No. 1,991,154.,granted Feb. 12, 1935, to Walter E. Irving., said vpatent showing thebroad idea of using an open mesh grating for .supporting the burden ofmotorized tra'lc as applied lto the special case of bridges.

The best type of construction at present known to me embodying myinvention is illustrated in the accompanying two sheets of drawings inwhich,

Fig. 1 is `a cross section of a street construction showing my inventionemployed therein,

Fig. 2 is a plan View thereof with parts broken away. Y, Fig. 3*, is anIenlarged detail plan showing the preferred form or type of gratingmesh.

Fig. 4 is a horizontal section on line 4-4 of Fig. 1, showing the lowerroadway in plan lwith parts broken away, and a modified construction oftrench walls.

Fig. 5 is a detail vertical rsection on line 5-5 of Fig. 1, parts beingbroken away, and

Fig. 6 is a detail section on a Vertical plane showing a modifiedform ofprotecting covering for certain electric cables.

Throughout the drawings like reference characters indicate like parts.

Referring to Figs. l and 2 Vlf have indicated at 0 I, I, the sidewalksand at 2, 2, the curbs therefor, as in an ordinary street construction,but with said curbs carried to any necessary depth, as indicated at 24,24. A trench dug between said curbs is generally indicated at 3 asextending to a depth more than suicient to provide headway for asubmerged line of traffic, and I'I indicates an open mesh gratingsupported over said trench by transversashallow, relatively lightchannel irons I6, I6, turned up on edge and resting on beams I5, I5carried by widely spaced apart girders I4. Y

. 'I'hese girders, as shown, rest on ledges I9, I9, extending alongthefaces. of the trench side walls crete. In Fig. 1 these girders are shownas deep YI-beams and would be spaced apart a considerable distance whichwould be spanned by the plurality of lighter I-beams I5, the ends of thelatter being supported by said girders I4, as by angle plates 25, 25which may be. riveted or bolted 4to the webfportions of both, asindicated at 2B, 2,6. These girders I4 may also besupported at pointsintermediate of their ends as by vertical members I0 which, as shown inFig. 4,

may be VI-beams set on top of a wall r9, runningk n lengthwise of thetrench bottom 4 and approxi-f mately along` the central line thereof.Preferably such wall is pierced by a plurality nof wide arches 21, asshown in Fig. 5, so as to afford free passage from oneV side of thetrench bottom to the other for workmen and inspectors and free surfacedrainage from one edge to the other of said trench iioor.

The side faces of wall 9 and the lower side faces of walls 24, 24,preferably should have ledges I3, I3, formed therein and on whichchannel beams I I, I I, may have their ends supported. The foregoingdescribed structure, or some other equiv- 30 24, which usually would beconstructed of con- Y alent therefor, supports the lower grating roadwayl2. These channel beams may be heavier than those I6 supporting theupper grating i1 and may have wider flanges, as shown, to carry 5v` theweight of heavy trucks, in case the lower roadway is reserved for trucktraffic, While only lighter vehicles are permitted on the upper road-Way I1.

The gratings I2 and I1, particularly the latter,

10 should have from 50% to 80% of their surplus Y areas left open, theremaining percentages of such surface areas consisting of the upperedges of the bars and strips forming said grating.

If desired a lling of cement 28 or other mastic strip immediatelyadjacent each curb 2 to catch small objects which pedestrians may dropwhile o1 We pna vvq aruba omini nq infini' LLUG @19111132 l5 911@ H'9911109191121 @11G 191961. 91191.69 0l 9119111921199 ll 111111011691111G 1911190611 cmnm me isnm nella sim 2mb? 20 s2 m mum/m Van HoffenPatent No. 1,629,134, and when repairs to the water pipes, gas pipes andsewers are needed sections or panels of the lower deck 12 may be takenout by loosening and removing bolts connecting adjacent original panelsor sections, 5 or in the case of smaller openings they can be made byburning or chiseling out the rivets and cutting the grating bars andstrips so as to remove an area of any desired size which can be replacedand re-riveted in position after repairs to pipes 10 or sewers have beencompleted.

Also, either or both gratings I2 and I1 may have a hinged trap doorformed therein, as indicated at 30 in Fig. 4, perhaps one for each cityblock. 15

The depth of the trench below the lower grating should be suicient toaccommodate nearly all of the average winter snowfall in theneighborhood. The figures on such snowfall can always.

voor we time mi niet anni @sin 9111912 0i, ipe smet@ minier anemie nl weneitppoiins aponiq pe minoren; ro sccommoqes neemt su ps qebpp o; ppspiencp pelom ipe 1011161. tmpplOGK' IQ cssq er 3g in mit' s bsipsbz oneroi. @scp @nl a J i \a p vpgvlieq p91) gooi 11111111011111116111 s?111111 some of the fresh air in front'of-A them down throughthe uppergrating into the trench while sucking in behind them, upwards throughsuch upper grating, volumes of air from the trench in- ,terion This lastdescribed action Aof rapidly moving cars Von bridges built inaccord-ance wit-h the invention of the before mentioned Irving Pat-ent1,991,154A has been found most effective in Adrying the gratings afterany wetting thereof, and in keeping them dry and clean between rains,thus preserving them from rusting and rendering repainting .largelyunnecessary. My invention would perform those useful functions also byvirtue of its automatic Ventilating action above pointed Aout quite aseffectively as have the other bridge deckings now and for some time indaily use.

Various modiiications in details of construction, other than thosehereinbefore suggested, could be made in special cases without departingfrom the underlying principles of my invention as hereinbeforeexplained, and hereinafter pointed out in the appended claims, so longas a selfdraining storage space is provided for average snowaccumulations below an open mesh grating serving as a street pavement.

A pavement composed of perforated plates would not serve the moreimportant purposes and objects of my invention since free spaces forexpansion and contraction would have to be left between the looselyfastened abutting ends of such relatively short plates, and such plateends would soon be rendered still looser under the impact of traffic andbegin jumping up and down under the rapidly moving cars. Also thepercentage of area of open spaces through such plates could not be madelarge enough to render their surfaces self-cleaning and non-skid incharacter as are grating roadways formed of narrow strips set on edge asherein described. The absence of non-skid action in any road surfaceformed of discontinuous plate-like surfaces has been proven by theexperience with a bridge decking formed of spaced-apart, horizontallyextending, tongues of plate metal. After a short period of use it wasfound necessary to give such decking at least a little non-skidcharacter by welding little knobs of metal on the upper surface of everysuch horizontally extending tongue, and subsequent designs of that typeand included a similar hump or projection formed integral with the uppersurface of each such tongue.

Having described my invention, I claim:

1, A highway structure particularly adapted for motorized traffic andadapted to effect automatic removal of falling snow from the paththereof comprising the combination of a foundation therefor including atrench of relatively large cross section extending lengthwise below thesurface of such highway and provided with a waterproof bottom surface,together with means for draining the same, and an open mesh grating, theopen spaces in which have an aggregate area exceeding fifty percent. ofits total area, supported over said trench at the proper level foraccommodating said traffic and serving as a selfcleaning screen formingthe surface of a major portion of such highway affording open passagethrough the same for light and air to the lower level and for rain andsnow to the drain below, together with a second grating supported insaid trench at a distance from the bottom thereof sufficient to allowroom for men working beneath it and at a distance below said firstmentioned grating sufficient. to afford room for motorized 'trailicthereon.. Y 1

2. A struct-ure such as defined in claim l combined with paved sidewalksproperly Curbed and extending along either side of such highway, and inwhich :sa-id trenchv and upper grating extend from one :of suchcurbs .tothe other.

3. A combination such as defined in claim 1 in which said :gratingsareformed of a plurality of metal strips all vset on edge with their uppersurfaces .all .lying in `substantially 'one and the same plane, and`many of their lower edges supported .along spaced-apart lines, saidstrips being held together at all points of contact one with anotherwithzsufhcient rigidity to. form a unitary structure presenting areticulated upper surface serving as a roadway for the traffic.

4. A combination such as defined in claim 1 in which said gratings areformed of a plurality of metal strips all set on edge with their uppersurfaces all lying in substantially one and the same plane, and many oftheir lower edges supported along spao-ed-apart lines, said strips beingheld together at all points of contact one with another with sufficientrigidity to form a unitary structure presenting a reticulated uppersurface serving as a roadway for the traflic; said metal strips being oftwo classes, the members of one of which classes are straight bars ofuniform depth extending parallel to the line of such traiiic, while themembers of the second class are bent into wave-like form and areinterspersed between said straight bars.

5. A combination such as defined in claim 1 in which said gratings areformed of a plurality of metal strips all set on edge with their uppersurfaces all lying substantially in one and the same plane and many oftheir lower edges supported along spaced-apart lines said strips beingheld together at all points of contact one with another with sufficientrigidity to form a unitary structure presenting a reticulated uppersurface serving as a roadway for the traffic, said grating being in theform of continuous, structurally integral sections extending from curbto curb and from one expansion joint to another substantially remoteexpansion joint.

6. A combination such as defined in claim 1 in which the entire exposedbottom surface of said trench is slightly inclined downward toward oneside, whereby storm sewer openings need only be provided along thatside.

'7. A combination such as defined in claim l in which said trench hasconcrete side walls and the supports for said lower grating comprise athird wall extending along substantially the medial line of said trenchand ledges formed on the inner surfaces of all said walls, together witha plurality of spaced-apart beams extending transversely of said trenchand having their ends resting on said ledges.

8. A combination such as defined in claim 1 in which said trench hasconcrete side walls Aand the supports for said lower grating comprise awall extending substantially along the medial line of said trench andledges formed on the inner surfaces of all said walls, while thesupports for said upper grating comprise vertically extending metaluprights set on said center wall.

9. A combination such as defined in claim 1 in which said upper gratinghas a greater percentage of open mesh space than said lower grating andthe supporting structure for said upper grating comprises a plurality oftransversely extending, parallel, narrow sills set about fteen inchesapart on which said grating may rest directly with the straight barsthereof extending lengthwise of the roadway; whereby a grating ofsufficient lightness and openness to permit oommercial fabrication andensure free air circulation may be used, but still support the heavywheel loadings of modern motor trucks.

l0. A structure designed for use in a city str-eet and adapted to eiectautomatic removal of falling snow from the surface thereof comprising incombination an open mesh grating forming a major portion of aself-cleaning street surface reserved for vehicular traffic and givinglight and ventilation to a relatively deep and wide trench locatedbeneath said grating, a secy trench and having a plurality of relativelylarge openings therein to afford passage therethrough for such Workmen.

BURTON A. PRINCE.

